Configuration Information [Automatically generated, do not change]: Machine: x86_64 OS: linux-gnu Compiler: gcc Compilation CFLAGS: -g -O2 -fstack-protector-strong -Wformat -Werror=format-security -Wall uname output: Linux latitude 5.15.0-2-amd64 #1 SMP Debian 5.15.5-2 (2021-12-18) x86_64 GNU/Linux Machine Type: x86_64-pc-linux-gnu
Bash Version: 5.1 Patch Level: 16 Release Status: release Description: Even if descriptions of situations where this problem occurs may sound contrived, those situation exist and require me to catch this problem with additional code: a: defining an empty function will throw a syntax error b: defining an empty bodies flow control construct will thow a syntax error While it may be debatable whether such construct could serve any purpose (they actually can), perceived lack of purpose doesn't qualify them as syntactically wrong. They aren't. Would they be syntactically wrong, the syntax error would continue to exist after adding a harmless "no operation" equivalent. You may justifiable ask "so why not simply use the workaround by adding a no operation equivalent" - answer is that it may not be me in person creating a function or a flow control construct - the script may do too, in accordance with input it received (this is the mentioned part where the description may sound contrived, but isn't). Therefore I must protect the script at this point from generating empty functions or flow control constructs. You may have guessed here that this is going towards some sort of meta programming, and a fuller view of the reason for reporting the bug can be obtained at https://github.com/Bushmills/yoda, specifically at https://github.com/Bushmills/yoda/issues/7 Measures to circumvent the problem can be found in file https://github.com/Bushmills/yoda/blob/main/yoda at around line 1900 (at this time) on those lines with text "empty function" in the description Repeat-By: bar() { ; } foo() { if true; then ; fi; } foo() { while :; do ; done; } Fix: In cases where this problem arises, I tend to synthesise the closest approximation of a "no operation" I know about, which is ":": bar() { :; } foo() { if true; then :; fi; } foo() { while :; do :; done; }
